Convert Steam ID text to Int64

CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;

public class Program
{
	public static void Main()
	{
        string input = "STEAM_1:1:66138017";
		//string input= "";
		var id = TranslateSteamID(input);
		
		//Correct result according to https://developer.valvesoftware.com/wiki/SteamID :
		// 76561198092541763
		Console.WriteLine(id);
	}
	
	public static Int64 TranslateSteamID(string steamID)
	{
		Int64 result = 0;
		
		var template = new Regex(@"STEAM_(\d):([0-1]):(\d+)");
		var matches = template.Matches(steamID);
		if (matches.Count <= 0) return 0;
		var parts = matches[0].Groups;
		if (parts.Count != 4) return 0;
		
		Int64 x = Int64.Parse(parts[1].Value) << 24;
		Int64 y = Int64.Parse(parts[2].Value);
		Int64 z = Int64.Parse(parts[3].Value) << 1;
		
		result =  ((1 + (1 << 20) + x) << 32) | (y + z);		
		return result;
	}
}